Claude Opus 4.6 vs Claude Sonnet 4.6

Choose Claude Opus 4.6 if you want…

• ✓Higher intelligence (Artificial Analysis index 46)

Choose Claude Sonnet 4.6 if you want…

• ✓Faster output (~44.1 tokens/sec)
• ✓Lower price ($6 / 1M blended)

Claude Opus 4.6

Opus 4.6 is the model researchers and engineers reach for when the problem genuinely cannot be chunked — loading an entire codebase, a year's worth of literature, or a complex multi-part investigation into a single session of up to 750,000 words. It tops Terminal-Bench 2.0 among frontier models for agentic coding tasks and leads BrowseComp for hard-to-locate information retrieval, reflecting a design philosophy built around sustained, autonomous work rather than quick exchanges. Scientists have noted roughly double the accuracy on computational biology and structural chemistry tasks versus its predecessor. The tradeoff is speed: at 38.8 tokens per second, it feels noticeably slower than alternatives during interactive back-and-forth. The 1M-token window is also still in beta, and users report meaningful performance degradation well before hitting its ceiling. Best suited to high-stakes tasks where depth matters more than pace.

Claude Sonnet 4.6

Sonnet 4.6 sits at the sweet spot where coding and agentic work get done without paying Opus prices. On SWE-bench Verified it scores 79.6% — within one point of Opus 4.6 (80.8%) — at roughly a third of the cost, which is why developers running automated pipelines tend to reach for it first. The self-correction training is the headline improvement: when a tool call fails, the model recognizes and recovers rather than cycling through the same error. Users also praise the 1M-token context window for swallowing entire codebases or large document sets in a single pass. The honest caveat is that this context window has edges — retrieval quality degrades on adversarial tests beyond about 700K tokens, so vector-based RAG is still the safer bet for critical long-context searches. Speed is also a known tension: at 44 tokens per second, it runs slower than the median for its tier, which can feel noticeable in real-time applications. Still, for teams that need high-quality code generation, browser automation, and multi-step agentic workflows without Opus-level spend, Sonnet 4.6 is the practical default.